Amid jokes, comments and laughter about what they'd do once Giffords, D-Ariz., returns to Washington, "we were holding her hand and she was responding to our hand-holding," Gillibrand, D-N.Y., told reporters aboard Air Force One late Wednesday. "She was rubbing our hands and gripping our hands so … we knew she could hear and understand what we were saying and she moved her leg, and so we knew she was responding."

Giffords was shot through the head Saturday when a gunman opened fire during her "Congress on the Corner" event at a Tucson grocery store. Six people were killed and 13 people, including Giffords, were injured.

A memorial was conducted Wednesday in Tucson to honor Giffords and the other victims of Saturday's rampage. President Obama announced the news about Giffords eyes opening during the event. Even more surprising, Gillibrand said, as the lawmakers continued to crack wise, "she started to open her eyes, literally."

Actually, it was one eye -- one was buried under bandages because it was injured by the gunfire -- that Gillibrand, Wasserman Schultz, D-Calif., and other visitors saw flutter.

"You have to recognize, her eyes hadn't opened -- we didn't know that -- and so she started to struggle," Gillibrand said. "So her eye is flickering. … And we didn't -- I didn't know what that meant."

Giffords' husband, NASA astronaut Mark Kelly, urged her to open her eyes and a physician in the room "is like perking up" and people are gathering around the congresswoman's bed, Gillibrand said.

"And she's struggling and she's struggling and it's a good -- we couldn't figure it out, maybe 30 seconds, where she's really trying to get her eyes open," the senator said. "And then she finally opens her eyes and you could she was like desperately trying to focus and it took enormous strength from her."

Kelly was happy and excited, Gillibrand said, "and we're crying because we're witnessing something that we never imagined would happen in front of us."

Both legislators said Kelly was encouraging Giffords to give him the thumbs-up sign, which she didn't do.

"(Instead) of giving the thumbs up, she literally raises her whole arm," Gillibrand said, demonstrating for reporters. "And then she reaches out and starts grabbing Mark and is touching him and starts to nearly choke him -- she was clearly trying to hug him."

After they were shooed from the room so Giffords could rest, Wasserman Schultz said neurosurgeon Dr. Michael Lemole told the women, "I just witnessed the impact of friendship and what you guys (did) ... here today."

"(Really), it felt like a miracle," Wasserman Schultz said. "It felt like we were watching a miracle. … And just the strength that you could see just flowing out of her to get -- it was like she was trying to will her eyes open."

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